The Stong Complex: A reassessment

Re-examination of the eastern and northern partsofthe Stong Complex has shown that there are three plutonic components. The earliest two phases are in part highly deformed in a manner similar to that of the marginal country rocks. The third phase, a distinctive set of pink granites. is underformed. Around the granitic rocks a contact aureole is developed in which the highest grade rocks are of low amphibolite facies. The numerous metasedimentary and metavolcanic enclaves within the granites have upper amphibolite facies mineralogy. Available evidence suggests that the intense dynamothermal metamorphism and deformation recorded in both sedimentary and some plutonic rocks resulted from forces generated by emplacement of the granitic rocks. At least the last part of the intrusive history of the Stong Complex took place in Late Cretaceous times; the age of the earlier phases is uncertain but lies within the time-frame Triassic to Late Cretaceous.